The Flash: Barry's Biggest Weakness Creates A Glaring Plot Hole

Contains spoilers for "The Flash"

"The Flash" is a superhero movie that juggles a lot of big ideas, and with all the balls it has in the air, it's not all that surprising that the film might drop one or two. However, it's one thing to overlook small stuff like, say, the fact that dangerous criminal Al Falcone (Luke Brandon Field) hears certain embarrassing secrets from both Batman (Ben Affleck) and The Flash (Ezra Miller), and everyone seems to be cool with it. What's harder to ignore is the fact that "The Flash" uses much of its first half to establish a very specific limiter to Barry Allen's speed powers ... and then spends the rest of the movie ignoring it altogether.

From his very first moment onscreen, it's clear that Barry needs to eat a whole lot to maintain his pace. With great power, in his case, comes great metabolism — and if he neglects to keep up with his calorie intake, his powers effectively vanish. This creates tension in the opening hospital rescue scene, as a nearly depowered Barry has to smash a free-falling vending machine for a super-fast emergency refueling session. The Flash's constant need to feed is further established when the younger alternate-universe Barry gets his powers and finds out that his body is screaming for sustenance after just a short superspeed session. 

With this elaborate setup, it's easy to assume that the protagonist's specific dietary requirements are an important plot point that comes into play later down the line. However, around the time Michael Keaton's Batman enters the fray, the whole calorie-counting thing starts disappearing into the background, to the point that every Flash in the final act can function for absurd amounts of time without as much as a chocolate bar. 

The food situation is still somewhat in play in the movie's second act, as younger Barry continues to eat whenever he can. We see him noisily wolfing down Bruce Wayne's (Michael Keaton) multiverse-explaining spaghetti dish, commandeering his other self's coffee mug, and even accidentally overhearing older Barry's reason for time-traveling while tucking into a snack in a nearby hidey-hole. 

However, when push comes to shove, neither Barry seems to remember that they constantly need to refuel. In the massive final fight against General Zod's (Michael Shannon) forces, both versions of The Flash spend a prolonged period in the heat of the battle without having a single bite to eat, raining blows and throwing lighting blasts all over the place with gusto. And that's before the younger Flash figures out how to time travel. Once that aspect of the plot comes into play, they start rewinding the same battle over and over — once again, with no food in sight. 

Though the main Flash soon realizes that it's futile to fight the battle with slightly different tactics but the same outcome over and over again, he still runs the gamut more than once — and based on what the early parts of the movie establish, he should be pretty drained by the time he stops. Still, even if we assume that the Flashes simply had a huge meal before the big battle, it still doesn't explain the younger Barry's exploits. As the main Flash keeps imploring him to stop his time shenanigans, the alternate-universe one just keeps going, running through the same time loop over and over again. Not only does he rewind himself back into the heat of the battle non-stop, but he also picks more and more injuries with every turn, forcing his body to heal around the debris that gets stuck in him. At no point is there any indication that he eats even nearly enough to fuel any of these metahuman feats.

And then there is the Dark Flash, alternate Barry's older self who has been stuck in the same self-imposed time loop for an unspecified, absurdly long time. Just like his younger self, he's extremely driven, and the implication is that he's been trying to figure out how to win the battle non-stop all these years. The battlefield still doesn't have any food, so it remains unclear how he manages to do this without any calories — after all, he's clearly not stuck in a timeless state himself, seeing as he's aged and deteriorated into a monstrosity. 

Of course, "The Flash" is all about time travel, and the younger alt-universe Barry specifically says that he considers time meaningless, so it's technically possible that he and Dark Flash keep leaving the battlefield for a quick burger run every few hundred miles. However, the fact that the movie's final third doesn't address the various Flashes' need to maintain their calorie intake breaks the very rules the movie itself took great pains to establish.